Theory Tuesdays -- What do Wikipedia, car-pooling, couch surfing, and social bookmarking have in common?

Last fall, I worked for four months in Google, Zürich. It was a fun and enriching experience, indeed. The opportunity to learn and contribute to the technology that is used by millions of people daily is quite exciting.

Besides enjoying the Google-life, during my days in Zürich, I was invited by two artist friends, Silvan Käelin [1,2,3] and Philip Matesic [4,5,6]), to give a talk about my PhD thesis research at Perla Mode -- as part of the Theory Tuesdays project.

Philip organizes a weekly event at Perla Mode named Theory Tuesdays. The goal is to bring together artists, researchers (of multiple disciplines), and the public to discuss a variety of topics such as art, technology, society, and their intersection.

I received the invitation with surprise and interest. It was a new experience to talk to an audience completely outside my field of research. Also, it was a chance to receive feedback (from such non-technical group) about what I think it is a relevant topic of study.

The idea was to have a middle ground between what I have been investigating (i.e., techniques to assess the value of contributions in peer production systems [pdf]) and a the broader topic that could interest the attendance.

Therefore, it seemed appropriate to introduce the notion of peer production systems [7], hint the questions I am interested in answering in this context, and asking the participants related questions such as: how do they perceive the value of information they consume online? do they often perceive themselves contributing to others by producing information online? what is the main incentive to do so? What are the aspects they take into account to decided whether an information provider produces value to them?

I am glad that the "talk" turned into a lively conversation about about all these questions and other aspects related to online peer production. We covered topics from the basic notion of social production (and why it works so well in certain scenarios), passed through specifics about the utility of tagging (e.g., classification languages may emerge through collaboration), and talked about the intuition behind the techniques I am designing to assess the value of contributions in social tagging systems.

Although anecdotal, it was possible to observe from the discussion two explicit trends on the perception of value of online peer-produced information: novelty and trust on the information producer. These aspects came up in the discussions as crucial to the users to assess the value of peer-produced information. It is important to note that the information consumer's interest is an implicitly aspect considered in the value assessment.

The observations are somehow intuitive, but for me it was quite important and helpful to have a first-hand discussion with the real users of the systems I study. It does help one to tune the questions to ask and where the relevancy of one's research. I hope to have more opportunities like this. Thanks to Silvan and Philip for the first one.

References:

[1] One Man
[2] Lagoa do Ouro
[3] Temps de Poussiére (Time of Dust)
[4] An Bonus
[5] Mau Series
[6] To Don Pedro with Mr. Gonzalez
[7] Y. Benkler. "The Wealth of Networks: How Social Production Transforms Markets and Freedom"

Assessing the Value of Contributions in Tagging Systems

During the past two and a half months, I have been visiting the InWeb/UFMG at Belo Horizonte - MG - Brazil. Besides enjoying the great 'Cozinha Mineira', in this opportunity, we studied the problem of assessing the value of contributions in social tagging systems, and took the first steps towards a solution. The ideas will be presented in an article at the 2nd IEEE International Symposium on Social Intelligence and Networking (SIN-10) in 20-22August 2010. Next stop: to give a talk at the Laboratório de Sistemas Distribuídos (UFCG).

Abstract -- Assessing the value of individual users' contributions in peer-production systems is paramount to the design of mechanisms that support collaboration and improve users’ experience. For instance, to incentivize contributions, file-sharing systems based on the BitTorrent protocol equate value with volume of contributed content and use a prioritization mechanism to reward users who contribute more. This approach and similar techniques used in resource-sharing systems rely on the fact that the physical resources shared among users are easily quantifiable. In contrast, information-sharing systems, like social tagging systems, lack the notion of a physical resource unit (e.g., content size, bandwidth) that facilitates the task of evaluating user contributions. For this reason, the issue of estimating the value of user contributions in information sharing systems remains largely unexplored. This paper introduces this problem and takes the first steps towards a solution. More precisely, it presents a framework to design algorithms that estimate the value of user contributions in tagging systems, proposes three complementary success criteria for potential solutions, and outlines the methodological evaluation challenges.

Individual and Social Behavior in Tagging Systems

As part of a much broader investigation on the peer production of information, Individual and Social Behavior in Tagging Systems [1] is a recent work that focuses on the quantitative aspects of tag reuse, item re-tagging and the implicit social relation inferred from the similarity of user interests.

The observations point to interesting directions on the design of systems, such as recommendation systems, that aim at exploiting past user activity. For instance, it providers quantitative evidence why item recommendation tends to be less efficient than tag recommendations in these systems (based on the relatively higher level of tag reuse, compared to the item re-tagging).

I must mention that this work is a result of a collaboration with an enthusiastic team: Nazareno Andrade, David Condon, Adriana Iamnitchi and Matei Ripeanu,

Reference:

[1] Elizeu Santos-Neto, David Condon, Nazareno Andrade, Adriana Iamnitchi and Matei Ripeanu. "Individual and Social Behavior in Tagging Systems". In the 20th ACM Conference on Hypertext and Hypermedia. Torino, Italy, June 29-July 1, 2009.

Content Sharing with Good Privacy Control

This is a follow up on the previous post.

Open Tag is a tool where users do have the option to select what is private and to which degree. Moreover, users may withdraw completely from the system by removing their activity traces.

Digital Libraries and User Attention


This past week, I attended to the JCDL'2007 (Joint Conference in Digital Libraries) and the CAMA'2007 (International ACM/IEEE Workshop on Contextualized Attention Metadata).

Since I cannot comment every single interesting paper that I've seen and discussed about (there are so many), I will point two interesting papers:

The first, which was also the very first presentation of the conference, World Explorer: Visualizing Aggregate Data from Unstructured Text in Geo-Referenced Collections (presented by Rahul Nair). This is a cool tool built on top of Flickr geotagging features. It is really nice to see how many applications are possible considering on-line communities like Flickr and del.icio.us that incorporate tagging features.

The main opportunity explored by the authors is to use geo-reference to cluster content. Besides a simply photo sharing mechanism, I think geotagging also opens up several research challenges/opportunities on designing applications for urban sensing.

The second paper was Can Social Bookmarking Enhance Search in the Web? (presented by Y. Yanbe).

The authors propose the introduction of what I would call a "Ranking Aggreagator" mechanism between the user, Google PageRank and del.icio.us ranking. Thus, their observation is that extremely fresh web pages tend to get low PageRank, but they may have a fair number of bookmark occurrences in del.icio.us. Therefore, they propose a combination of both ranking schemes to improve the ranking of fresh pages and allow the user to get good mix of 'reputable' pages via PageRank and popular pages on del.icio.us. Actually, I wondered if a combination of Google search history and the user interest sharing could be combined to provide better personalized search results.

I also participated to an interesting workshop, CAMA'2007, organized by Erik Duval, Martin Wolpers and Jehad Najjar.

The first talk by Seth Goldstein was exciting, possibly because it shows the incredibly large number of business opportunities are orbiting on-line social networks and how much value there is on online users attention

Joe Pagano from the Library of Congress presented some results on measuring the audience of a newly launched web site. His main finding was that more visitors come from blogs than from search engines, just to reinforce the intuition on the blog influence on the information consumption in the Web.

Personally, a positive aspect of this workshop was to identify possible applications that may validate our preliminary studies on interest sharing in collaborative tagging communities. For example, an extension on Joe Pagano's work would be the application of our interest sharing graph to understand how these visitors relate to each other and whether they from sub-communities of interest.

Also, Erik Duval made a nice comment on the fact that the large number of unique users we have found in our investigation over CiteULike and Bibsonomy may still present rich information to recommendation systems, even though these users are not connected to any island of interest we depicted in the interest sharing graph (more details here).

This is a brief summary of what I have seen this past week. Now, a lot of ideas to refine and put in practice...

Issues on Online Reputation


The Information Week has an interesting article on the issues involving the proliferation of web communities which are built around user generated content and mechanisms to build user reputation.

Web Credibility: Hard Earned, Harder To Prove
by J. Nicholas Hoover

The Art of Tagging Libraries


It turns out that there is a system that allows users to tag virtual library catalogs.

Thanks to my fellows at OpenTag.

The system is called PennTags and it is developed by people at University of Pennsylvania.

The Art of Tagging


This seems a very interesting idea on how to extract the perception of public about objects, particularly, art works. Furthermore, it is also a clever way to understand what is the vocabulary actually used by the majority of the audience to describe the art works.

The Art Museum Social Tagging Project

There is a workshop paper about it in the program of WWW2006 Conference:

Investigating social tagging and folksonomy in art museums with steve.museum

An interesting application of the same idea would be to add tagging capabilities to online library catalogs, where users of public libraries could categorize items that they've read (or intend to) by using tags online. This could give a clue about the content of the item, a kind of highly compacted review.